Performance of labyrinth-stratified water-storage system for heating and cooling

Conference · Fri Jan 01 00:00:00 EST 1982

OSTI ID:5111846

Wildin, M W

The feasibility of storing heating or cooling capacity in thermally-stratified water contained in rectangular concrete tanks has been demonstrated in this project. For the approximately cubical tanks, which were 4.6 meters deep, and for the flow rates which were employed in a diurnal charge-discharge cycle, thermoclines about three feet thick were routinely established during charging and discharging phases of an operating cycle. Initially, vertical internal partitions were installed in the tanks during construction to prevent direct streaming from inlet to outlet and to maximize the active fraction of storage volume. However, it was found that these partitions were unnecessary, and they leaked water, so they were eventually removed. Also, the original blunt inlet/outlets were replaced with linear diffusers designed to introduce water into the tanks and remove it at low velocity and with a relatively uniform distribution. These diffusers were located at diagonally opposite horizontal corners of a tank. Thermal efficiency was evaluated for periods long enough that changes in internal energy of storage could be neglected relative to total energy flow to and from storage. The efficiency realized from cooled storage was in the range from 80 to 90 percent, while that for heated storage was in the range from 65 to 81 percent with the most frequent value being near 70 percent. The higher efficiency of cooled storage is due to several factors, including lower temperature differences to produce energy flow across the boundaries, less internal mixing in storage when the partitions were present and shorter average residence times of energy in storage. Evaluation of the performance of cooled storage using tanks with no internal partitions was being performed in the 1982 summer cooling season.

• Research Organization: Oak Ridge National Lab., TN (USA); New Mexico Univ., Albuquerque (USA). Dept. of Mechanical Engineering
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 5111846
• Report Number(s): CONF-820827-16; ON: DE82020817
• Resource Relation: Conference: Energy storage contractors review meeting, Arlington, VA, USA, 23 Aug 1982; Other Information: Portions of document are illegible
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
BUILDINGS
AIR CONDITIONING
SPACE HEATING
TANKS
BAFFLES
STRATIFICATION
THERMAL EFFICIENCY
WATER
SENSIBLE HEAT STORAGE
CONCRETES
DESIGN
FEASIBILITY STUDIES
TEMPERATURE DISTRIBUTION
BUILDING MATERIALS
CONTAINERS
CONTROL EQUIPMENT
EFFICIENCY
ENERGY STORAGE
EQUIPMENT
FLOW REGULATORS
HEAT STORAGE
HEATING
HYDROGEN COMPOUNDS
MATERIALS
OXYGEN COMPOUNDS
STORAGE
320100* - Energy Conservation
Consumption
& Utilization- Buildings